Latch mechanism



June 12, 1956 H. A. BLEAM LATCH MECHANISM 4 Sheets-Sheet 1 Filed July1l, 1952 2 2 m@ a y J mi N 1. "0T A f f ,m W a w June 12, 1956 H. A.BLEAM 2,750,219

LATCH MECHANISM Filed July ll, 1952 4 Sheets-Sheet. 2

INVENTOR.

June 12, 1956 H. A. BLEAM LATCH MECHANISM 4 Sheets-Sheet, 3

Filed July l1I 1952 June 12, 1956 H. A. BLEAM LATCH MECHANISM 4Sheets-Sheet. 4

Filed July 11, 1952 INVENTOR. eczzfz n 2,750,219 Patented June 12', 1956LATCH MECHANISM Howard A.. Blearn, Chicago, Ill., assigner to AdmiralCorporation, Chicago, lli., a corporation of Delaware Application July11, 1952, Serial No. 298,265

7 Claims. (ci. z -19s) This invention relates to latch mechanism forreleasably retalning two members together, there being relative movementbetween the members when the latch mechanism is unlatched. Morespecifically, the invention comprehends latch mechanism for a door toclose an opening in a casing, the operation of latching the door toretain it in closed position and/or unlatching it for its movement withrespect to the opening being adapted to be carried out without the aidof conventional handles either 011 the door itself or in connection withthe latch mechanism.

Although latch mechanisms of the foregoing description are known to theprior art, their structures are comparatively intricate and consequentlyexpensive of manufacture and subject to maladjustrnent.

Owing to the present invention latch mechanism of the foregoingdescription has been provided which is of simplified construction andwhich is consequently less expensive of manufacture and less subject tomaladjustment. By the present invention a latch mechanism is provided inwhich not only is less metal required for its construction but by'itsuse metal door knobs, pulls or handles are dispensed with. Otheradvantages will be apparent from the specification which is descriptiveof the accompanying drawings, in which:

Fig. l is a fragmentary sectional view of a door and casing with a latchmechanism about to be engaged taken on line 1--1 of Fig. 2;

Fig. 2 is a fragmentary sectional view at right angles to Fig. l;

Fig. 3 is a view corresponding to Fig. l, with the latch mechanism inengaged position;

Fig. 4 is a View also corresponding to Fig. l, the keeper being shown ina still different position;

Fig. 5 is a perspective view of a second embodiment of the invention;

Fig. 6 is an elevational View of the keeper unit of the secondembodiment, parts being broken away to reveal other parts;

Fig. 7 is a view corresponding to Fig. 6, the latch mechanism being in adifferent position;

Fig. S is an elevational View of a third embodiment of the invention, inunlatched position;

Fig. 9 is a view corresponding to Fig. 8, the parts being shown inlatched position;

Fig. l is a perspective view of the slider housing;

Fig. l1 is a perspective View of the slider;

Fig. l2 is a vertical section on line 12-12 of Fig. 9;

Fig. 13 is a fragmentary sectional view taken on line 13-13 of Fig. 1'6and showing a fourth embodiment of the invention;

Fig. 14 is a view corresponding to Fig. 13 showing the keeper ina'different position;

Fig. l is a view corresponding to Fig. 13 showing the keeper in a stilldifferent position; and

Fig. 16 is a fragmentary sectional View taken on line 16-16 of Fig. 13.

` The mechanism shown in Figs. -1 and 2 includes a frame, housing orcasing 2 defining an opening 3 which may be in a cabinet adapted to beclosedby a door 4 movably anchored to the casing in any convenientmanner such as by one or more hinges 6. The door is therefore movablefreely in a predetermined course relative to the opening 3 and may belimited in its inward movement'by a stop portion or surface 7 on thecasing. For a purpose later to be described, the door is biased, to alimited extent, away from the stop surface 7, by suitable resilientmeans carried by the door and adapted to engagethe surface 7 or carriedby the casing and adapted to engage the door as it is moved intoadjacent relationship to the stop surface. In the embodiment referredto, the resilient means takes the form of a leaf spring 8, one end ofwhich is anchored on the inner side of the door Vin a recess 9 out ofwhich the spring slopes outward and terminates in a free end 11 adaptedto engage the surface 7 and thereby to be deected into the recess whenthe door is brought into engagement with `the stop surface.

The door 4 is adapted to be releasably retainedV Vin closed relationshipto the opening 3 by novel latch mechanism. It comprises a pin, stud orfollower 12 on the edge of the door 4, opposite the hinged edge, and akeeper 13 pivoted at 14 to the casing 2. In order that the keeper 13 mayoffer no obstruction to movement of the door 4, but may cooperate withthe pin 12, the keeper is positioned within a recess 16 in the casing atthe edge of opening 3. The mechanism by which the keeper is caused tomove about pivot 14 will now be described.

Preferably struck from sheet metal, the keeper 13 is further definedlargely by curved surfaces the function and nature of which will laterbe indicated. Although the thickness of the stock for the keeper is notcritical, it may be from 1/16 to 1,4; of an inch in thickness. Suitablekeepers were made from sheet brass approximately V32 of an inch inthickness. A part of the edge of keeper 13 is dened by a cam surface 17which spirals outward about the pivot 14 from a stop surface 18 at theinner end of said cam surface. The keeper 13 also includes a hookportion or arm 19, generally arcuate in extension about the pivot 14,and which terminates in a free end 21. Arm 19 is spaced from the cam 17by a channel 22 extending from a throat 23, between the free end 21 andcam 17, to the stop surface 18. Although the throat 23 is of width onlyslightly greater than the diameter of pin 12, the width of the channelbroadens from the throat 23 into a socket 24 on the inner side of thearm 19, the purpose of the socket being later to be indicated. From thesocket 24 the width of the channel 22 gradually diminishes to the stopsurface 18.

In order that there may be cooperation between the follower 12 andkeeper 13, said follower is so positioned, on the door, that it isadapted to be carried through a plane, in which the vertical axis of thekeeper 13 is disposed and, through a plane slightly higher than theplane of the keepers horizontal axis, depending on the curvature of cam17. Following engagement of cam 17 by the pin 12, the force of thelatter is followed by clockwise rotation of the keeper 13, due, ofcourse, to a tendency of said cam to ride over the pin. The stop surface18 is thus carried into engagement with or into the proximity of thefollower depending on the force with which the door is closed. When theforce necessary for closing the door is spent or neutralized by thereactional force of spring 8, said spring urges the door outward.Whether the follower 12 then latchably engages the arm 19 or not dependson the violence with which the door was closed and the rapidity withwhich it consequently rebounds by the force of the spring.

To understand the manner in which the latching is effected, it should beunderstood that the keeper 13 is rotated to its Fig. 1 position bygravity at a predetermined rate when swung away from this position andreleased. The rate at which the pin 12 may move to the left, however(Fig. 1), is governed by the violence with which it is moved manuallyinward. It therefore follows that with suflicient rebound from itsinnermost position (Fig. 3), the follower may intercept the arm 19before gravity has had time to move it below the course through whichthe follower is carried in moving outward. Consequently, the arm 19engages the pin 12 and thus operatively resists movement of the dooroutward. At this point, it is noteworthy that there is adequate frictionbetween arm 19 and pin 12, augmented by the spring, to operativelyresist the urge of gravity to rotate keeper 13 from its Fig. 3 to itsFig. 1 position. Thereafter, the spring releasably retains the follower12 in engagement with arm 19; that is, in latched engagement with saidarm. Moving the door closed and gradually allowing it to be opened bythe spring at a rate slow enough for the end 21 to be lowered below theplane through which follower 12 is adapted to be carried is not, ofcourse, accompanied by any latching engagement of the follower by thekeeper. Thus it follows that to unlatch the follower 12 from keeper 13it is only necessary to depress the door against the spring 8 adequatelyto enable gravity to rotate the keeper counterclockwise to its Fig. 1position.

The second embodiment of the invention (Figs. 5, 6 and 7) includes a camor keeper 26 in combination with a housing 27 therefor, the cam beingsimilar to cam 13 of the embodiment previously described. The housing ispreferably formed of sheet metal and includes a rectangular end portion28 from opposite edges of which uniformly spaced-apart side walls 29 and31 extend. The wall 29 is flanged perpendicularly toitself at 32 andextends to the wall 31. The wall 31, on the other hand, also bears aflange 33, perpendicular thereto, by which the housing is adapted to beanchored to a cabinet or door. The flange has holes, one of which isindicated at 34, for reception of anchor screws or bolts. The keeper 26is, of course, rotatably supported and this is on a shaft 36, the endsof which are fixed to the walls 29 and 31. The shaft 36 is so disposedwith respect to a clearance slot 37, in the wall 29, and companionclearance slot 38, in the wall 31, that when there is movement between afollower or pin 39 and the keeper 26 a cam surface 41 on the keeper maybe engaged by the follower to rotate the keeper as previously indicated.

The follower 39 is supported by a bracket 42 which is also preferablystruck from sheet metal having a flange 43 which is slotted at 44 inwhich the pin 39 is received and in which said pin is adjustably clampedby a nut 46 on either side of the flange 43. Additionally, the follower39 may be adjusted longitudinally thereof, both by the aid of the nuts46 and/ or a pair of slots 47 through which screws are adapted to passinto the support for bracket 42.

Within the housing 27 is provided resilient means to urge the followeraway from the keeper 26. Said means may comprise a spring 48, coiledabout a rod 49 the ends of which are supported by walls 29 and 31 of thehousing 27. The spring 48 includes an arm 51, normally engaged by thewall 32, and an arm 52 in engagement with the wall 28, to resistuncoiling of the spring (Fig. 6). As the follower 39 is carried towardthe keeper, said follower first engages the arm 51 of spring 48 which isadditionally deflected (Fig. 7) and performs the function of maintaininglatched engagement between an arm 53, of the keeper 26 and the follower39. Latching and unlatching of the mechanism is performed in the samemanner as has already been described in connection with the embodimentfirst referred to.

The third embodiment of the invention, illustrated in Figs. 8 to l2inclusive, comprises a keeper unit 54 and a follower unit 56. Thefollower unit comprises a support member 57 (Fig. 10) which is generallyrectangular in formation and preferably struck from sheet metal. [t hasflanges 58 struck outwardly from either side thereof, both of whichconverge and extend away from the mem- .4 ber 57. The purpose of thearms 58 is to embrace (Fig. l2) a pair of diverging arms 59 extendingfrom opposed edges of a striker member 61, also of generally rectangularconformation and preferably formed from sheet metal. In the spacebetween the arms 59 is supported a compression spring 62 one end ofwhich engages a lug 63, struck vertically from the surface of thestriker member 61, while the remaining end of said spring is adapted toengage another lug 64 on the central portion S7 of the support member.Normally, as when the follower unit 56 is out of cooperative associationwith keeper unit 54 the force of spring 62 biases the lug 63 intoengagement with a pin or follower member 66 fixed to the central portion57 toward the end thereof.

The follower is adapted to be carried into a slot 67 in the keeper unit54, o-r the slot carried over the follower depending on whether thekeeper unit or follower unit is mounted on the door. Regardless of whichmounting is adopted the spring 62 is compressed as the follower entersthe slot 67, since lug 63 is wider than said slot. In the course of thisoperation pin 66 engages a cam surface 68 on a keeper 69, identical instructure to the keeper 13, and journaled on a shaft 71 which is infixed relationship to a keeper housing 72.

The operation of latching and uulatching the units 54 and 56 to eachother is an previously described, the cam 69 being adapted to be rockedagainst the force of gravity from its normal position (Fig. 8) to andbeyond its Fig. 9 position to which it is returned by its own weight andwherein an arm 73 retains the follower 66 against the force of spring62. Once the follower 66 is released from the arm 73, the spring 62moves the keeper unit 54 in a direction away from the follower unit.

In the fourth embodiment of the invention, shown in Figs. 13 to 16inclusive, a keeper unit 75 includes a keeper 76 which is adapted to bemaintained in either of two positions by spring pressure. In order thatthis may be carried out a frame 77 is provided which is formed fromsheet metal. The frame 77 includes a rectangular base portion 78 fromone side of which a flange portion 79 extends to provide support for anarm 81 integral with the flange portion and uniformly spaced from thebase portion 78 to afford accommodation therebetween for the keeper 76.A shaft 82 between the arm 81 and base portion 78 provides bearingsupport for the keeper 76. Since spring pressure, later to be described,is employed to releasably station the keeper 76 in one of its positions,it is unnecessary that the center of gravity of the keeper be eccentricto its pivotal support as in the previously described illustrations ofthe invention. Consequently, the keeper unit 75 is adapted to be mountedin any operative position on either a casing 83 or a door 84.

In order that the keeper 76 may be moved to either of the positionsreferred to, the arm 81 carries a spring 86. It is generally arcuate information and may be of some resilient material such as steel musicwire. One end of the spring 86 passes through a lug 87, at the free endof arm 81, thence through a second lug 88, on said arm to which thespring end is clamped by a set screw 89. The other end of the spring 86passes freely through one of a plurality of holes 91 at the edge of thekeeper 76, the particular hole used being best determined by test. Whileso confined, the spring 86 constantly exerts a downward force on thekeeper tending to urge the keeper in a counterclockwise direction (Fig.13) thereby providing one extreme keeper position. When the keeper 76has been rotated clockwise by cooperation of a cam 92 thereon with afollower 93, on the door, the clockwise motion of the cam is arrested inproximity to another eXtreme position by the follower (Fig. 14). Betweenits two extreme positions, the keeper passes through an over-thecenterposition from either side of which the spring 86 is adapted to bias thekeeper toward its nearest extreme position. From the position indicated(Fig. 14) the follower 93 is moved byv a spring 94 (Fig. 16), acounternpart of spring 8 (Fig. l) slightly to the left, which op-'permitted by a socket 97 on the arm 96. It will now be apparent thatmoving the door 84 slightly in an inward direction so that follower 97is carried momentarily to the right (Fig. l) frees the keeper formovement counterclockwise by the spring 86 to its Fig. 13 position sothat the door is free to be opened.

Although my invention has been described in four ernbodiments thereof, Iam aware that numerous and extensive departures may be made from thestructures disclosed without departing from the spirit or scope of theinvention.

I claim:V

1. A door latch having a follower for the door and a latch for the dooropening disposed opposite to the follower, said latch comprising a platepivotally supported and freely revolvable about a fixed axis, a curvedtongue on said plate providing a spiral-shaped channel between `saidtongue and said plate having an open throat at one end in spacedvrelation to said' axis and extending spirally inward relative to saidaxis to a'stop surface formed on the end of said channel opposite tosaid throat, said tongue being formed with a curved follower engagingsurface which is curved about the pivot for the latch, said plate havinga gravitational center spaced from said axis being operable to normallypresent said follower engaging surface to said follower, the radius ofsaid follower engaging surface relative to said axis being greatest at apoint spaced from the end of the tongue and less on either side thereof,said tongue arranged to move to a follower engagmg position uponrotation of said plate and said curved follower surface arranged toengage and retain said f ollower upon movement of said plate to followerengagmg position.

2. A door latch having a follower for the door and a latch for the dooropening disposed on the casing opposite to the follower, said latchcomprising a plate plvotally supported and freely revolvable about afixed axls, a curved tongue on said plate providing a spiralshapedchannel between said tongue and said plate havmg an open throat at oneend in spaced relation to said axls and extending spirally inwardrelative to said axis to a stop surface formed on the end of saidchannel opposite to said throat, said tongue being formed with a curvedfollower engaging surface which is curved about the pivot for the latch,said plate having a gravitational center spaced from said axis beingoperable to normally present said follower engaging surface to saidfollower, the radius of said follower engaging surface relative to saidaxis being greatest at a point spaced from the end of the tongue andless on either side thereof, said tongue arranged to move to a followerengaging position upon rotation of said plate and said curved followersurface arranged to engage and retain said follower upon movement ofsaid plate to follower engaging position, and spring means between thedoor and casing resiliently holding said door toward an open positionwith said follower seated at the point of greatest radius of saidfollower engaging surface on said tongue.

3. The combination with a first member movable toward and beyond alatching position relative to a second member, of resilient meansassociated with one of the members for constantly urging the firstmember backward through its latching position whenever said rst memberhas been moved therebeyond, latching mechanism operative when the firstmember is moved in one manner to latchably couple the members togetherand capable of being unlatched when said first member is moved n anothermanner including an adjustable follower on said movable member, a latchunit for the other of said members comprising a casing connected to saidother member, a plate pivotally supported to and freely revolvable abouta fixed axis on said casing and disposed oppositely to said follower, acurved tongue on said plate providing a spiral-shaped channel betweensaid tongue and said plate having an open throat at one end in spacedrelation to said axis and extending spirally inward relative to saidaxis to a stop surface formed on the end of said channel opposite tosaid throat, said tongue being formed with a curved follower engagingsurface which is curved about the pivotal axis of the plate, said platehaving a gravitational center spaced from said axis being operable tonormally present said follower engaging surface to said follower, theradius of said follower engaging surface relative to said axis beinggreatest at a point spaced from the end of the tongue and less on eitherside thereof, said tongue being in an unlatching position and saidfollower engaging surface being positioned for engagement with saidfollower before said members are at their latching position, saidfollower engaging said follower engaging surface to move said tongue toa follower engaging position when the first member is moved beyond itslatching position, movement of the first member back to its latchingposition quickly enough serving to latchably engage said follower bysaid tongue before said tongue can be returned to its unlatchingposition thereby to latchably secure the members in latched relation toeach other, said members being unlatched from each other when the firstmember is moved against the resilient means slowly enough to enable thetongue of said plate to move to its unlatched position.

4. The device as defined in claim 3 and wherein the follower comprises abracket carried by the movable member and a follower element adjustablycoupled to said bracket.

5. A door latch for a door hinged for movement toward and beyond alatching position relative to a closable member defining a door openingcomprising a bracket secured to said door, a follower adjustably coupledto the bracket for axial and lateral adjustment relative thereto, saidbracket also having anchor slots therein for passage of anchor boltstherethrough and into said door, by which said bracket is adjustablyclamped to said door, a casing connected to said closable memberdisposed opposite to said follower and having spaced-apart walls and aslot in at least one of said walls for entrance of said follower,resilient means supported within said casing and extending past the slotfor constantly urging the follower out of the casing to its latchingposition, a plate pivotally supported between said walls and freelyrevolvable therebetween, a curved tongue on said plate providing aspiral-shaped channel between said tongue and said plate having an openthroat at one end in spaced relation to said axis and extending spirallyinward relative to said axis to a stop surface formed on the end of saidchannel opposite to said throat, said tongue being formed with a curvedfollower engaging surface which is curved about the pivotal axis for theplate, said plate having a gravitational center spaced from said axisbeing operable to normally present said follower engaging surface tosaid follower, the radius of said follower engaging surface relative tosaid axis being greatest at a point spaced from the end of the tongueand less on either side thereof, said follower upon said door beingmoved toward said closable member beyond said latching position beingcarried thereby against the resistance of said resilient means intoengagement with said follower engaging surface on said plate andoperable to swing said tongue to a latching position, said door beinglatchably coupled to the closable member when said door is released tomove backward before said tongue can be returned to its unlatchedposition, said door and closable member being unlatched from each otherwhen backward movement of said door is at a rate slower than it can bemoved by the resilient means to free said tongue to its unlatchableposition.

6. A door latch for a closing member hinged for movement toward andbeyond a latching position relative to a closable member comprising ahousing fixed to said closing member, a follower on the housing, aspringbiased movable striker, guide means on the housing to slidablyanchor the striker thereto and confine said striker for movement intogreater and less proximity to the follower, a casing in said closablemember, said casing being formed with at least one wall having therein aslot extending horizontally from one of its edges and being capable ofaccommodating the follower, a plate pivotally supported and freelyrevolvable about a fixed axis on said casing, a curved tongue on saidplate providing a spiralshaped channel between said tongue and saidplate having an open throat at one end in spaced relation to said axisand extending spirally inward relative to said axis to a stop surfaceformed on the end of said channel opposite to said throat, said tonguebeing formed with a curved follower engaging surface which is curvedabout the fixed axis of said plate, said plate having a gravitationalcenter spaced from said axis being operable to normally present saidfollower engaging surface to said follower, the radius of said followerengaging surface relative to said axis being greatest at a point spacedfrom the end of the tongue and less on either side thereof, and saidfollower engaging surface being normally presented to said follower atthe level of said slot, said follower being arranged to extend into theslot and into engagement with the follower engaging surface to swing thetongue upward adequately to confine said follower between said tongueand said follower engaging surface against the resistance of said biasedstriker.

7. A device as defined in claim 6 and wherein the follower on said doorextends laterally from the housing on one end thereof, and resilientmeans are supported by the housing to provide for biasing the strikerinto association with the follower.

References Cited in the le of this patent UNITED STATES PATENTS 652,828Bailey July 3, 1900 837,811 Ebbeson Dec. 4, 1906 1,589,874 Ewing June22, 1926 1,896,363 Johnson Feb. 7, 1933 2,427,134 Gronbeck Sept. 9, 19472,458,751 Voight Jan. 11, 1949 2,548,046 Nottingham Apr. 10, 1951FOREIGN PATENTS 9,895 Great Britain 1886 16,566 Great Britain 189135,364 Denmark Dec. 7, 1925 86,655 Sweden `Tune 23, 1936

